Cadence Encounter

GUI from farm hosts to submit host

Cadence Encounter uses X-windows, so you need to be sure the X server on the submit host can accept client connections from the farm machines.

In olden days, this was as simple as:

% xhost +

You still have to do this, but there is more too. See below.

Alas, due to heightened security concerns, most recent (2009) Linux distributions start the X-server with the -nolisten tcp option, so it does not even listen for clients, except on the loopback interface, in the expectation that clients from remote hosts will be tunneled through an SSH connection.

You can verify that this is the case running the following and looking for -nolisten tcp in the output.

% ps auxww | grep X

You can use the gdmsetup GUI to edit the config to enable listening on TCP ports (Usually 6000 for display :0), or edit the config files directly. It is better to use the config UI because the file location varies.

If you get messages from Encounter like _IceTransSocketUNIXConnect: Cannot connect to non-local host you can probably work around it by submitting the job in an xterm, after setting env-var DISPLAY to the host:displaynumber for your workstation.

% setenv DISPLAY your-host:your-displaynum
% nc run -Ix xterm -e encounter


% nc run -e 'D(DISPLAY=host:N)'  xterm -e encounter